Recently, low cost smart phone based thermal cameras are being considered to be used in a clinical setting for monitoring physiological temperature responses such as: body temperature change, local inflammations, perfusion changes or (burn) wound healing. These thermal cameras contain uncooled micro-bolometers with an internal calibration check and have a temperature resolution of 0.1 degree. For clinical applications a fast quality measurement before use is required (absolute temperature check) and quality control (stability, repeatability, absolute temperature, absolute temperature differences) should be performed regularly. Therefore, a calibrated temperature phantom has been developed based on thermistor heating on both ends of a black coated metal strip to create a controllable temperature gradient from room temperature 26 &deg;C up to 100 &deg;C. The absolute temperatures on the strip are determined with software controlled 5 PT-1000 sensors using lookup tables. In this study 3 FLIR-ONE cameras and one high end camera were checked with this temperature phantom. The results show a relative good agreement between both low-cost and high-end camera’s and the phantom temperature gradient, with temperature differences of 1 degree up to 6 degrees between the camera’s and the phantom. The measurements were repeated as to absolute temperature and temperature stability over the sensor area. Both low-cost and high-end thermal cameras measured relative temperature changes with high accuracy and absolute temperatures with constant deviations. Low-cost smart phone based thermal cameras can be a good alternative to high-end thermal cameras for routine clinical measurements, appropriate to the research question, providing regular calibration checks for quality control.

It is difficult to obtain quantitative measurements as to surface areas and volumes from standard photos of the body parts of patients which is highly desirable for objective follow up of treatments in e.g. dermatology. plastic, aesthetic and reconstructive surgery. Recently, 3-D scanners have become available to provide quantification. <p> </p>Phantoms (3-D printed hand, nose and ear, colored bread sculpture) were developed to compare a range from low-cost (Sense), medium (HP Sprout) to high end (Artec Spider, Vectra M3) scanners using different 3D imaging technologies, as to resolution, working range, surface color representation, user friendliness. The 3D scans files (STL, OBJ) were processed with Artec studio and GOM software as to deviation compared to the high resolution Artec Spider scanner taken as ‘golden’ standard. The HP Spout, which uses a fringe projection, proved to be nearly as good as the Artec, however, needs to be converted for clinical use. Photogrammetry as used by the Vectra M3 scanner is limited to provide sufficient data points for accurate surface mapping however provides good color/structure representation. The low performance of the Sense is not recommended for clinical use. The Artec scanner was successfully used to measure the structure/volume changes in the face after hormone treatment in transgender patients. <p> </p>3D scanners can greatly improve quantitative measurements of surfaces and volumes as objective follow up in clinical studies performed by various clinical specialisms (dermatology, aesthetic and reconstructive surgery). New scanning technologies, like fringe projection, are promising for development of low-cost, high precision scanners.

In the development of new near-infrared (NIR) fluorescence dyes for image guided surgery, there is a need for new NIR
sensitive camera systems that can easily be adjusted to specific wavelength ranges in contrast the present clinical systems
that are only optimized for ICG. To test alternative camera systems, a setup was developed to mimic the fluorescence light
in a tissue phantom to measure the sensitivity and resolution. Selected narrow band NIR LED’s were used to illuminate a
6mm diameter circular diffuse plate to create uniform intensity controllable light spot (μW-mW) as target/source for NIR
camera’s. Layers of (artificial) tissue with controlled thickness could be placed on the spot to mimic a fluorescent ‘cancer’
embedded in tissue. This setup was used to compare a range of NIR sensitive consumer’s cameras for potential use in
image guided surgery. The image of the spot obtained with the cameras was captured and analyzed using ImageJ software.
Enhanced CCD night vision cameras were the most sensitive capable of showing intensities &lt; 1 &mu;W through 5 mm of
tissue. However, there was no control over the automatic gain and hence noise level. NIR sensitive DSLR cameras proved
relative less sensitive but could be fully manually controlled as to gain (ISO 25600) and exposure time and are therefore
preferred for a clinical setting in combination with Wi-Fi remote control. The NIR fluorescence testing setup proved to be
useful for camera testing and can be used for development and quality control of new NIR fluorescence guided surgery
equipment.

Allergy testing is usually performed by exposing the skin to small quantities of potential allergens on the inner forearm and scratching the protective epidermis to increase exposure. After 15 minutes the dermatologist performs a visual check for swelling and erythema which is subjective and difficult for e.g. dark skin types. A small smart phone based thermo camera (FLIR One) was used to obtain quantitative images in a feasibility study of 17 patients
Directly after allergen exposure on the forearm, thermal images were captured at 30 seconds interval and processed to a time lapse movie over 15 minutes.
Considering the 'subjective' reading of the dermatologist as golden standard, in 11/17 pts (65%) the evaluation of dermatologist was confirmed by the thermo camera including 5 of 6 patients without allergic response. In 7 patients thermo showed additional spots. Of the 342 sites tested, the dermatologist detected 47 allergies of which 28 (60%) were confirmed by thermo imaging while thermo imaging showed 12 additional spots. The method can be improved with user dedicated acquisition software and better registration between normal and thermal images. The lymphatic reaction seems to shift from the original puncture site. The interpretation of the thermal images is still subjective since collecting quantitative data is difficult due to motion patient during 15 minutes.
Although not yet conclusive, thermal imaging shows to be promising to improve the sensitivity and selectivity of allergy testing using a smart phone based camera.

The significant increase of skin cancer occurring in the western world is attributed to longer sun expose during leisure time. For prevention, people should become aware of the risks of UV light exposure by showing skin damage and the protective effect of sunscreen with an UV camera. An UV awareness imaging system optimized for 365 nm (UV-A) was develop using consumer components being interactive, safe and mobile.
A Sony NEX5t camera was adapted to full spectral range. In addition, UV transparent lenses and filters were selected based on spectral characteristics measured (Schott S8612 and Hoya U‐340 filters) to obtain the highest contrast for e.g. melanin spots and wrinkles on the skin. For uniform UV illumination, 2 facial tanner units were adapted with UV 365 nm black light fluorescent tubes. Safety of the UV illumination was determined relative to the sun and with absolute irradiance measurements at the working distance. A maximum exposure time over 15 minutes was calculate according the international safety standards.
The UV camera was successfully demonstrated during the Dutch National Skin Cancer day and was well received by dermatologists and participating public. Especially, the 'black paint' effect putting sun screen on the face was dramatic and contributed to the awareness of regions on the face what are likely to be missed applying sunscreen.
The UV imaging system shows to be promising for diagnostics and clinical studies in dermatology and potentially in other areas (dentistry and ophthalmology)

During laparoscopic surgery, devices are require to either cut, ablate or coagulate tissue and veins with high precision and controlled lateral damage preferably in an one-for-all modality. The tissue interactions of 3 new treatment modalities were studied using special imaging techniques to obtain a better understanding the working mechanism in view of effective and safe application.
The Plasmajet produces a high temperature ionized gas 'flame' directed to the tissue surface at the tip of a 4 mm diameter rigid hand piece. The Lumenis DUO CO2 laser enables endoscopic laser energy delivery through a 1 mm outer diameter flexible hollow waveguide. The 2 µm 'Thulium' laser is delivered by (standard) 400 µm diameter optical fiber.
Thermal imaging and Schlieren techniques were used to assess the superficial ablative and coagulation effects these surgical instruments scanning at preset velocities and distances from the surface of biological tissues and phantoms . The CO2 was very effective in tissue ablation even at a distance up to 10 mm due to a very small diverging beam from the hollow waveguide. In contrast, the Thulium laser showed less ablation and increasing coagulation at larger distance to the tissue. The gas 'flame' of the Plasmajet spread the thermal energy over the surface for effective superficial ablation and coagulation. However, the pressure of the gas flow is substantial on the tissue surface creating turbulence and even indirect cooling.
The specific ablation and coagulation effects of the three treatment modalities have to be appreciate and the effective and safe application will depend on the preference and skills of the surgeon

The mechanism of action of the holmium laser lithotripsy is attributed to explosive expanding and imploding
vapor bubbles in association with high-speed water jets creating high mechanical stress and cracking the stone
surface. A good understanding of this mechanism will contribute to the improvement and the safety of clinical
treatments. A new method has been developed to visualize the dynamics of mechanical effects and fluid flow
induced by Holmium laser pulses around the fiber tip and the stone surface. The fiber tip was positioned near the
surface of a stone on a slab of polyacrylamide gel submerged in water. The effects were captured with high
speed imaging at 2000-10000 f/s. The dynamics of the pressure wave after the pulse could be visualized by
observing the optical deformation of a fine line pattern in the background of the water container using digital
subtraction software. This imaging technique provides a good understanding of the mechanical effects
contributing to the effectiveness and safety of lithotripsy and can be used to study the optimal fiber shape and
position towards the stone surface.

For infants and neonates in an incubator vital signs, such as heart rate, breathing, skin temperature and blood oxygen saturation are measured by sensors and electrodes sticking to the skin. This can damage the vulnerable skin of neonates and cause infections. In addition, the wires interfere with the care and hinder the parents in holding and touching the baby. These problems initiated the search for baby friendly 'non-contact' measurement of vital signs. Using a sensitive color video camera and specially developed software, the heart rate was derived from subtle repetitive color changes. Potentially also respiration and oxygen saturation could be obtained. A thermal camera was used to monitor the temperature distribution of the whole body and detect small temperature variations around the nose revealing the respiration rate. After testing in the laboratory, seven babies were monitored (with parental consent) in the neonatal intensive care unit (NICU) simultaneously with the regular monitoring equipment. From the color video recordings accurate heart rates could be derived and the thermal images provided accurate respiration rates. To correct for the movements of the baby, tracking software could be applied. At present, the image processing was performed off-line. Using narrow band light sources also non-contact blood oxygen saturation could be measured. Non-contact monitoring of vital signs has proven to be feasible and can be developed into a real time system. Besides the application on the NICU non-contact vital function monitoring has large potential for other patient groups.

With new fiber systems available for 3 &mu;m, Erbium lasers become more interesting for precise tissue ablation in a water
environment enabling new application in e.g. dentistry. The dynamics of explosive bubble formation was investigated at
2.78 &mu;m (Er,Cr;YSGG) and 2.94 &mu;m (Er:YAG), in relation to energy (10-50 mJ), pulse length (20–150 &mu;s) and fiber tip
shape (flat or taper). The dynamics of exploding and imploding vapor bubbles were captured with high speed imaging
(10 - 300 &mu;s range). Increasing the pulse length and energy, the vapor bubble became more elongated with an opaque
surface for flat tip fibers. Tapered fibers produced spherical vapor bubbles with an optically transparent surface expected
to be more forceful for creating mechanical effects in both hard and soft tissues. There was no significant difference
between bubbles formed at 2.78 &mu;m (Er,Cr;YSGG) and 2.94 &mu;m (Er:YAG).

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